gulf(What this really highlights for us is the staggering gulf between the intent of the design and the end result, which is all that really matters. If the design makes sense – if it's logical – but you still end up blasting your eyes with acid? It's bad design.polygon.com); wall of partition(между людьми В.И.Макаров)
abyss(a very deep or bottomless hole or chasm); chasm(a deep opening between high rocks etc. • The climber could not cross the chasm); deep(про́пасть); gap(про́пасть); wall of partition; be sunk(If he finds out that we've been disobeying him, we're sunk)
go out the window(о нематериальных вещах; Political Correctness has gone out the window in this strategic game – в этой стратегической игре пропала вся политкорректность Баян); go off the radar(VLZ_58)
be up the boohai(Lost or awry. A remote, out of the way or non-existent place, far from civilisation. Possibly derived from the place-name Puhoi. Sometimes used to describe a person's confused state of mind. New Zealand rural slang. "Where's Trevor?" "Up the boohai somewhere." VLZ_58)
has gone(мн.ч. – have gone • There'll be no commercial fishery on the Fraser this year. Where have all the salmon gone? – Куда пропал весь лосось?ART Vancouver)
there goes(There goes my weekend. -- Ну всё, пропали выходные. • Chico and his guys have moved in. There goes the neighbourhood... -- Всё, пропал наш район.ART Vancouver)
polygon.com); wall of partition (между людьми В.И.Макаров)